Study Design

Study Design:

Patient Populations:

Patients undergoing de novo percutaneous interventions at 15 participating clinical centers, including 10 that contributed to the original 1985-86 registry.

Primary Endpoints:

N/A

Drug/Procedures Used:

De novo percutaneous interventions

Principal Findings:

The National Heart, Lung, and Blood Institute (NHLBI) Dynamic Registry is meant to evaluate the evolving nature of interventional cardiology based on data from 15 participating clinical centers, including 10 that contributed to the original 1985-86 registry.
The design of the registry includes sequential waves of enrollment, each separated by 18 months. The first of 3 enrollment periods ended earlier this year, with investigators anticipating 2,000 patients per enrollment period.
In a preliminary comparison with the 1985-1986 registry, today's patients are significantly older (62.4 vs 58.2 years), more often female (32.5% vs. 25.5%) or non-white (12.9 vs 8.4%), and more likely to have a history of diabetes (25.8% vs. 13.5%) or hypertension (59.3% vs. 45.5%, all p<0.001). Today, there is also a trend toward treating 2 or more lesions per intervention.
While baseline characteristics suggest more advanced disease than among those treated in the mid-1980s, the angiographic characteristics, including the number of vessels treated and mean ejection fraction, have not changed significantly over time.
Significantly fewer patients in the new registry had angioplasty performed due to stable or unstable angina, but there was a more than two-fold increase in revascularization following acute myocardial infarction (MI). Consequently, fewer patients are being treated on an elective basis (62.5% vs. 75.4%), with more patients undergoing urgent procedures (24.3% vs. 18.8%) and a doubling of emergent interventions (13.2% vs. 5.8%).
The mean number of lesions attempted per procedure is less today than in the older registry (1.4 vs. 1.6 lesions). Likewise, the number of vessels attempted has declined, although more complex and severe lesions are being attempted (p<0.001). More lesions are being attempted in non- LAD locations today. Altogether, this suggests a shift to more selective angioplasty.
Despite the increased complexity, procedural success has increased (91.4% vs. 81.8%) and lesion outcomes have improved. Angiographic final residual stenosis is 11.9% vs. 33.1% in the original registry and the risk of abrupt closure has been reduced (2.0% vs. 3.1%, all p<0.01). There also have been significant improvements in complications, including MI, need for emergent bypass graft surgery, and/or death.

Interpretation:

Thus, more difficult lesions are being approached today with better angiographic and clinical outcomes.